Participants were recruited in Long Beach, California, between December 1988 and November 1990 as part of a longitudinal survey of HIV risk among injection drug users and their female partners. Only women 18 years of age or older who reported they had not used injection drugs within the previous 6 months were included in the study. Most females were black (56.9 percent), with the balance consisting of Latina (23.4 percent) and white (19,7 percent) women. All participants completed an AIDS Initial Assessment interview developed by the National Institute on Drug Abuse. Participants were offered HIV testing after the interview. A second interview was conducted to obtain in-depth, narrative descriptions of female sex partners' lives, their sexual and drug use behavior, their attitudes toward HIV and risk reduction strategies, and their relationships with partners. Levels of knowledge regarding HIV transmission and prevention were high, with an average of 81.8 percent correct on a 16-item test. Most women believed there was at least some chance they would become HIV infected. Substance abuse was prevalent; 67.2 percent used noninjection drugs, 44.5 percent used crack cocaine, and 32.1 percent reported prior use of injection drugs. About 20 percent had engaged in prostitution. Although AIDS knowledge was high, almost all respondents reported engaging in unprotected vaginal intercourse during the previous 6 months, and 6.6 percent reported anal intercourse without a condom. Most frequently stated reasons for nonuse of condoms were dislike by the male partner and/or personal dislike. A disturbing pattern of increased risk was noted among black interviewees who were more likely than Latinas or whites to have contracted syphilis, have multiple sex partners, engage in prostitution, use crack cocaine, and drink alcohol daily. 32 references and 2 tables (Author abstract modified)